Copper Alloy CuAg0.04(OF)-R320
Temper
EN CuAg0.04(OF)
Highest strength rod/section where stiffness and creep/softening resistance outrank formability.
Values for the R320 condition
Other CuAg0.04(OF) tempers and conditions
CuAg0.04(OF) is listed in 7 conditions; see the grade overview at CuAg0.04(OF).
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
R200Default annealed, soft rod & wire | Pick for maximum conductivity, deep drawing, bending, cold heading and vacuum-brazed assemblies. | 70 | 225 | 45 | 45 HB | 101 % IACS |
Thermomechanically controlled processed | Cheapest mill condition for stock that will be redrawn, forged or fully annealed by the user. | 80 | 220 | 40 | 50 HB | 100.5 % IACS |
light cold worked / quarter hard | Straight, stiffer rod that still bends and rivets; used for busbar links and machined contacts. | 180 | 260 | 25 | 72 HB | 100 % IACS |
Half hard drawn rod/profile | Common stocked drawn temper: good balance of strength, straightness and machining behaviour. | 200 | 270 | 15 | 80 HB | 99.5 % IACS |
hard drawn | Hard-drawn condition for commutator bars, rotor bars and contacts that must resist softening after soldering. | 270 | 320 | 8 | 95 HB | 98.5 % IACS |
R320This page extra hard drawn | Highest strength rod/section where stiffness and creep/softening resistance outrank formability. | 300 | 345 | 5 | 105 HB | 98 % IACS |
Hard drawn wire | Heavily drawn fine wire for windings and braids needing high tensile and softening resistance after enamelling. | 340 | 385 | 2.5 | 115 HB | 97.5 % IACS |
What is CuAg0.04(OF)-R320?
CuAg0.04(OF)-R320 is CuAg0.04(OF) in the R320 temper — highest strength rod/section where stiffness and creep/softening resistance outrank formability. CuAg0.04(OF)-R320 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 345 MPa (50 ksi) — stronger than 61% of copper alloy grades. Elongation at break is 5% and the elastic modulus is 118 GPa (17.1 Msi). CuAg0.04(OF)-R320 has a density of 8.93 g/cm³ (0.323 lb/in³), heavier than 82% of copper alloy grades. It melts at 1,083°C (1,981 °F). R200 is the default condition FabDigit quotes; R320 is available on request or by drawing note.
Advantages
- Conducts heat well — 391 W/m·K (225.9 BTU/hr·ft·°F), better than 98% of copper alloy grades
- High electrical conductivity — 98 % IACS, better than 94% of copper alloy grades
- Readily welded — 70/100, better than 85% of copper alloy grades
Limitations
- Limited ductility — 5%, worse than 93% of copper alloy grades
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
CuAg0.04(OF)-R320 properties
Typical room-temperature values for CuAg0.04(OF)-R320; 10 are specific to this condition. Other listed values are CuAg0.04(OF) reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
CuAg0.04(OF)-R320 has a density of 8.93 g/cm³ (0.323 lb/in³), heavier than 82% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Mechanical13
CuAg0.04(OF)-R320 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 345 MPa (50 ksi) — stronger than 61% of copper alloy grades. Elongation at break is 5% and the elastic modulus is 118 GPa (17.1 Msi).
Thermal6
CuAg0.04(OF)-R320 is rated for continuous service to 200°C (392 °F). It conducts heat at 391 W/m·K (225.9 BTU/hr·ft·°F), better than 98% of copper alloy grades. Thermal expansion is 17.7 µm/m·K (9.83 µin/in·°F).
Electrical3
CuAg0.04(OF)-R320 conducts electricity at 98 % IACS, better than 94% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 57% of copper alloy grades.
Sustainability4
Producing a kilogram of CuAg0.04(OF)-R320 takes about 60 MJ of energy and emits 4.2 kg of CO₂ — more than 69% of copper alloy grades. Typical recycled content is 8%.
Manufacturability8
CuAg0.04(OF)-R320's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability very good (70/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CuAg0.04(OF)-R320
Is CuAg0.04(OF) easy to machine?
Gummy, long-chipping: use sharp positive-rake carbide or PCD tools, high speed (200–400 m/min), light feeds with generous flood coolant; expect ~20 % of AISI 1212 productivity — switch to C14500/C14700 if heavy turning is needed.
Can CuAg0.04(OF) be welded?
TIG/MIG, EB and laser welding are all practical with no hydrogen-embrittlement risk; preheat 200–400 °C on thick sections to overcome the huge thermal conductivity, keep interpass low and avoid oxidising flames.
Can CuAg0.04(OF) be formed, bent or molded?
Excellent cold formability in R200 — deep draws, cold heading and tight bends; interstage anneal 400–600 °C, and remember silver only raises the softening point, it does not prevent recrystallisation above ~450 °C.
What surface finishes work on CuAg0.04(OF)?
Not anodisable; bright-dip, mechanically polish or electropolish, then tin/silver/nickel plate or lacquer to control tarnish; ideal substrate for hydrogen or vacuum brazing because there are no oxide inclusions.
CuAg0.04(OF) chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Agsilver addition raises softening/recrystallisation temperature | 0.03 – 0.05 | 0.04 |
| Ooxygen-free, ≤10 ppm | ≤ 0 | 5×10⁻⁴ |
| Pkept low to protect conductivity | ≤ 3×10⁻⁴ | — |
| Bi | ≤ 5×10⁻⁴ | — |
| Pb | ≤ 5×10⁻⁴ | — |
| S | ≤ 0 | — |
| Te | ≤ 2×10⁻⁴ | — |
| Se | ≤ 2×10⁻⁴ | — |
| Cu+Agminimum Cu+Ag per EN 1977 / EN 13601 | ≥ 99.95 | 99.97 |
| Cu | balance | — |
CuAg0.04(OF)-R320 — frequently asked
What is CuAg0.04(OF)-R320 used for?
CuAg0.04(OF)-R320 is typically used for electronic lead-frame stock, vacuum-brazed assemblies and high-temperature electronic conductors. In short: oxygen-free with silver; 101 % IACS conductivity; vacuum-braze compatible.
What is the yield strength of CuAg0.04(OF)-R320?
CuAg0.04(OF)-R320 has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 345 MPa (50 ksi) — stronger than 61% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.
Is CuAg0.04(OF)-R320 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Gummy, long-chipping: use sharp positive-rake carbide or PCD tools, high speed (200–400 m/min), light feeds with generous flood coolant; expect ~20 % of AISI 1212 productivity — switch to C14500/C14700 if heavy turning is needed.
Can CuAg0.04(OF)-R320 be welded?
Yes — weldability is rated very good (70/100). TIG/MIG, EB and laser welding are all practical with no hydrogen-embrittlement risk; preheat 200–400 °C on thick sections to overcome the huge thermal conductivity, keep interpass low and avoid oxidising flames.
What surface finishes work on CuAg0.04(OF)-R320?
Not anodisable; bright-dip, mechanically polish or electropolish, then tin/silver/nickel plate or lacquer to control tarnish; ideal substrate for hydrogen or vacuum brazing because there are no oxide inclusions.
Can CuAg0.04(OF)-R320 be formed, bent or molded?
Excellent cold formability in R200 — deep draws, cold heading and tight bends; interstage anneal 400–600 °C, and remember silver only raises the softening point, it does not prevent recrystallisation above ~450 °C.
What is the maximum service temperature of CuAg0.04(OF)-R320?
CuAg0.04(OF)-R320 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CuAg0.04(OF)-R200 and CuAg0.04(OF)-R360?
R200 is the default condition — pick for maximum conductivity, deep drawing, bending, cold heading and vacuum-brazed assemblies. R360: heavily drawn fine wire for windings and braids needing high tensile and softening resistance after enamelling. Yield strength is 70 MPa in R200 versus 340 MPa in R360.
Sources
- EN 1977 — Copper and copper alloys: copper drawing stock (wire rod) — CEN (2013)
- EN 13601 — Copper rod, bar and wire for general electrical purposes — CEN (2021)
- EN 13602 — Drawn round copper wire for electrical conductors — CEN (2013)
- ASTM B152/B152M and B187 — Copper (incl. C10500 silver-bearing oxygen-free) — ASTM (2019)
- CDA alloy datasheet C10500 (OFS, silver-bearing oxygen-free copper) — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials (copper) — ASM International (2005)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.